<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>条件渲染-练习</title>
    <style></style>
  </head>
  <body>
    <div id="root"></div>

    <script src="./js/react.development.js"></script>
    <script src="./js/react-dom.development.js"></script>
    <script src="./js/babel.min.js"></script>

    <script type="text/babel">
      //变量
      let isLogin = false; // 是否登录

      function loginFn(){
        if(!isLogin){
          <button className="login">请登录</button>
        }else{
          
          <p>已登录</p>

        }
      }
      
      let vdom=<div>
        {loginFn()}
        </div>

        ReactDOM.render(vdom,document.querySelector('#root'))

      
    </script>
  </body>
</html>
